Biofuels Reviewer Electives PDF

Reviewer Electives Biofuels Fuels Materials that store Potential Energy (used as heat energy) Uses A. Transportation Globally, 25% of energy demand and nearly 62% of oil consumed Cars and trucks Aircraft Off-Road Equipment...

Reviewer Electives Biofuels Fuels Materials that store Potential Energy (used as heat energy) Uses A. Transportation Globally, 25% of energy demand and nearly 62% of oil consumed Cars and trucks Aircraft Off-Road Equipment Small Engines B. Power Generation - 60% of power generated comes from fossil fuel C. Fossil fuels will be soon exhausted But, replenished fuel sources (Electric Cars, Solar Power, Wind Power or biofuels) What is biofuel? Any hydrocarbon fuel produces from organic matter Liquid fuel that is developed from plants or animal waste Common commercially used biofuels are bioethanol, biodiesel, and biomethane ○ Bioethanol (Sugaem algae, sugar beet) ○ Biodiesel (Vegetable oil, algal lipids, animal fats) ○ Biomethane (Organic material, sewage, agriculture waste, domestic waste) History 1890, Rudolf Diesel, made biodiesel from vegetable oil 1970 and 1980, Environmental Protection Agency (fuel should be free from sulphur dioxide 1998 EPA allowed biofuel as alternative source of petrol 2010 production of biofuel reaches 105 billion liters 2011, european countries where largest that made biodiesel almost 53% Biofuel Feedstock Soybean Corn  Sugarcane Sugar beet Switchgrass Jatropha Camelina algae Cassava Palm oil Animal fat Agricultural waste Advantages of Biofuels Cost Source material Renewability Security Economic simulation Lower carbon emissions Disadvantages of biofuels Production carbon emissions High Cost Food Prices Food Shortages Water use Advantages of biofuels over fossil fuels Lower Emissions Green gas Renewable Biogradable Safer Positives of biofuels Biodiesel is about 90% petroleum diesel Ethanol is about 50% of gasoline Butanol is about 80% of gasoline Biofuels burn cleaner than fossil fuels Biodiesel is sulfur free Biodiesel has fewer polycyclic aromatic hydrocarbons (linked to cancer) Classification of biofuels 1st generation Biofuels: conventional biofuels (sugar, starch , vegetable oil) 2nd generation Biofuels: Sustainable feedstock (Advanced biofuels) 3rd generation Biofuels: Extract mostly from algae. Types of biofuels 1st generation biofuels A. Bioalcohol Bioethnol Alcohol made from fermentation, mostly carbohydrates Cellulosic biomass Substitute petrol fuel for road transport vehicles Colorless and clear liquid According to UNCTAD, brazil uses pure ethanol in 20% of their vehicles and 22 to 26% ethanol-petrol blend in the rest of vehicles CO emission from automobiles decreased from 50 g/km in 1980 to 5.8 g/km in 1995 USA and Australia use 10% ethanol blend India is 4th largest producer and government mandated 5% ethanol blend Applications of bioethanol Transport fuel to replace gasoline Fuel for power generation by thermal combustion Fuel for fuel cells by thermochemical reaction Fuels in chemical industry Blending ethanol with small portion of gasoline is more cost-effective B. Biodiesel Variety of ester-based oxygen=nated fuels derived from natural, renewable biological sources Biodiesel operates in compression ignition engines like petroleum diesel Number of carbon atoms (10 to 21) Biodiesel produces 100% less SOx than petroleum Prepared by transesterification Reduces carbon dioxide emissions by 80% Smell is more pleasant Less dangerous to put in vehicle fuel tank as its flash point is (300 F) as opposed to petroleum diesel (150 F) Application of Biodiesel Railway usage Aircraft Use As a heating oil Cleaning oil spills Biodiesel in generators Vehicles  Parameters Bioethanol Biodiesel Process Fermentation Transesteriification Environmental Benefit Both Reduce greenhouse gas emissions Compatibility Blended E85% B100% Cost Cheaper More Expensive Gallons per acre 420 gallons per acre 60 gallons per acre soybeans Energy Provides 93% more net Produces only 25%more energy per gallon net energy Biodiesel in jatropha tree Can be cultivated anywhere along canals, roads, railway tracks on border Grown in high aas well as low rainfall High rainfall yield is more Mainly at altitude (0-500 cm) with average annual temperature above 200 C. Jatropha provides: Prevention of soil erosion Soil improvement Poverty reduction Renewable energy Promotion to labors Biodiesel: first trial run on train First successful trial run of a superfast passenger train was conducted on December 31, 2009 Delhi, Amritsar shatabli express used 5% of biodiesel fuel. Railway annual fuel bill = Rs 3400 crores (for diesel) 10% mixture with diesel = reduced 5% substitution is accepted C. Biobutanol The term biobutanol refers to butanol made from renewable resources (grain or cornstalks by fermentation process) Bacteria; Solventogenic Clostridia Similar to gasoline than ethanol  Butanol Applications Gasoline (as an additive) and brake fluid (formulation component) Solvent for paints Plasticizers - improve how plastic material processes Coatings- as a solvent for a variety of applications Chemical intermediate or raw materials - for other chemical of plastics Textiles - as a swelling agent from coated fabric Cosmetics - makeup Butanol can be used in car D. Biogas Gas produced by a breakdown of organic matter in the absence of oxygen Biomass is a biological material derived from living or recently living organisms Renewable source Mixture of CH4, CO2 and other gasses Used as domestic purpose Produced by anaerobic decomposition Gasses methane, hydrogen and carbon monoxide can be combusted or oxidized. Typical Composition of Biogas Gas Molecular Formula % Methane CH4 50-75 Carbon Dioxide CO2 25-50 Nitrogen N2 0-10 Hydrogen H2 0-1 Hydrogen Sulfide H2S 0-3 Oxygen O2 0-2 Two types of Anaerobic Digestion Mesophilic Process > 25-38 C for 14-30 days Thermophilic Process > 50-60 C for 12-14 days Produced from Anaerobic digestion in anaerobic digesters Biogas Plant Hydrolysis: Complex organic matter is decomposed into simple soluble organic molecules  Fermentation or Acidogenesis: Generation of intermediary products such as short chain fatty acids Acetogenesis: Acetate production Methanogenesis: Methane Production Advantages Biogas Reduced air and water pollution More environmentally friendly fertilizers Application of biogas Cooking Lighting Fuel engine Biofuels by regions International Organizations such as IEA Bioenergy IEA (International Energy Agency) Established in 1978 (improving cooperation) UN National Biofuels forum (Brazil, China, India, Pakistan, south africa, US, european commission) Russia also has 22% of world’s forest In 2010 Russian pulp and paper maker said they would be producing pellet Biofuels currently make up 3.1% of the total road transport By 2020, 10% of the energy used in UK Road and Rail transport Conventional biofuels are likely to produces between 3.7 and 6.6% of the energy needed in road, advanced biofuels could meet up to 4.3% of the UK’s renewable transport fuel target by 2020. E. Syngas Syngas Cogeneration/ Combined Heat and Power Also known as synthesis gas, synthetic gas, or producer gas Can include biomass (wood gas), plastic, coat, municipal waste. Can be configured in a combined power generation Created by gasification or pyrolysis of carbonaceous Gasification can occur in man made vessel, or alternatively could be conducted as in underground coal gasification Benefits of syngas utilization in gas engines Generation of renewable power Conversion of problematic wastes to useful fuels Economical onsite power production and reduced transmission losses Reduces in carbon emissions Synthesis Gas Composition challenges Highly dependent upon the inputs to the gasifier  Hydrogen gas is much quicker to burn than methane Faster combustion in the engine could lead to potential of pre-ignition The output of engine is reduced to between 50-70% of its typically natural gas output (i.e. 1,063 engine running on natural gas is comparable to maximum 730 kW engine on synthetic gas) Syngas Composition Substance Composition H2 20-40 CO 35-40 CO2 25-35 CH4 0-15 N2 2-5 Advantages Fueling Gas Engines with Syngas Independent Power Supply Reduced energy cost, greater predictability and stability Efficient and Economic Combined heat and electricity supply Best suited for an electrical efficiency compared to other power generation Best suited for an electrical output range of a few hundred kW up to 20-30 MW Low Gas Pressure required Alternative Disposal of a problem Substitute to conventional fuels Syngas Competence Clarke Energy has comprehensive experience with gas technology, about 30GE Jenbacher gas engines now run on either coke gas or LD converter gas. Synthesis Gas can be produced from a variety of sources. (Gas- to- liquids), (Coal to liquids), (biomass to liquids) all rely on the catalytic conversion of syngas. Hydrogen from syngas The water-gas-shift reaction CO + H20 CO2 +H2 = -41 kJ/mol CO is used as reductor to shift syngas entirely to H2 (and CO2)  Syngas to methanol Methanol is a versatile intermediate for chemical industry, served as fuel. Methanol is also used in transesterification of vegetable oils to produced biodiesel. Syngas to synfuels: The Fischer-Tropsch Synthesis Also known as FTS, converts syngas into hydrocarbons which forms gasoline, diesel, jet fuel, and chemical Forms GTL and CTL in South Africa, Qatar, Malaysia, china. Reaction conditions includes temperature between 200 and 350 gd. C The exothermic and dealing with heat Algae Biofuels From 1978 to 1996, the us NREL experiment with using algae as a biofuel A self-published article by micahel briggs, at the UNH Biofuels Group The oil-rich algae can then be extracted from the system processed into biofuels F. Solid biofuels Term “ solid biofuel” can be a bit misleading because many people associate biofuels with advanced refining chemical processes. Production : No production necessary since it is often in convenient form. Wood: Constitutes majority of biomass that is burned for fuel and comes in the forms of firewoods,charcoal etc. energy dense. Has an energy density of around 14-15 MJ/kg if burned with 100% efficiency. Animal Dung: Can be found in area where wood is scarce, renewable. Cow dung has 50% of methane and 30% CO2. energy density is 12 MJ/kg if burned with efficiency.